Final answer:
The correct term for an issue localized to an operator's host or VM that hinders sortie tasks is a 'malfunction.' This term is commonly used to describe failed operations of systems in various technical fields.
Step-by-step explanation:
A weapon system malfunction is any issue localized to an operator's host or VM that prevents one crew member from accomplishing sortie tasks. When answering the question, the choice that best fits the description provided is malfunction, since it denotes an instance where a system or component fails to operate correctly. The term malfunction is used across various technical disciplines to describe a scenario where equipment or systems are not performing as intended, which can hinder the ability to complete assigned tasks or missions in a military context.